Manufacture of tertiary-alkyl-substituted aromatic derivatives



Patented Feh12t1935 I m I I I I P ENT F CE g MANUFACT E or: .TERTIARY-ALKYL-SUB- s rlru'r zn AROMATIC DERIVATIVES Ralph P. Perkins, Andrew Dietzler, and Joseph TLLiindquist, Midland, Mich.-, assignors to The Y DowChemical Company, Midland, Mich., a cor-l partition of Michigan F r No Drawing. 'Appli'cation October 29,1931, 1

, Serial No. 571,856 I 4 I gs Claims. (o1. 260 5154) 1 I The present invention relates to improved.p'ro or a'steam jacket forintroducing heat 1:01am] cedurefor making tertiary alkyl-substituted.arecharge, if necessary,'to complete the reaction.

maticcompounds, such as tertiary alkyl benzenes Meansare also provided to takeoff gaseous reor thecorresponding alkyl-substituted phenols. action products and conduct'the same to another The commercial process for the manufacture, reaction chamber. Initially'the reaction between I for instance, of para-t'ertiary-butyl phenol as a the primary components may be effected at room Specific e ample of the class of compoundsin temperature, and is allowed to proceed until prequestion consists in condensing tertiary butyl pitation of Sol d p (3011131611665- Model;

chloride with phenol in the presence of a cata ate heating may then be resorted to for main-- l ryst Such as anhydrous ferric chloride or alumitaining themixture inafiuid condition until the. 1 num chloride; The reaction commences readily reaction is p td, e temperature a vi y upon simply bringing the componentsv together, not e e 0 after Which the p d: being accompanied by an active'fevolution of hynot is worked up in known manner for separadrogen chloride gas, which carries along with it tion of a purified tertiary-butyl phenolproduct.

In order to avoid loss of the latter, accordingly, n yd o n Chloride is rapidly evolved and it is necessary to recover the chloride from the passes out I through the exit passage carrying acidgasl. The treatment of the corrosive exit With it (vapors of the butyl-chloride. Commonly gases from the reaction for recoveryof the valasmuch as '10 to '15 percent of the butyl chlouable butyl chloride therefrom as ordinarily ride present may be removed from the reactor in 2 carried out, however, involves troublesome ma the exit gases. I Such gases are led toa second nipulation and the'useof'special equipment made reactor, already referred to, where they are ab of acid-resistant material, and in the end there sorbed in abody of'tertiary' butyl alcohol. The

. is more. or;less loss. of. .butyl chloride as well as acid reacts directly with the alcoholat ordinary thenecessity of disposing of the hydrogen ChlQ-j temperatures to produce the tertiary butylchloride. I Q I I ride, while the butyl chloride vapors accompany- .We have now found thatthe aforesaid diihculing the acid are condensed therein. At the beties and disadvantages may be. entirelyoverginning of the absorption the temperature of come, or avoided n a simple andeco'nomical the liquid may be allowed to vary between room manner by scrubbing or otherwisev contacting temperature and 60-70 0., but as'conv'ersion'of the exit gases with tertiary} butyl alcohol. alcohol to chloride approaches completion, the Thereby the butyl chloride vapors are condensed mixture should be cooledio a temperature inaand' dissolved and the hydrogen chloride reacts terially below the boiling point of the chloride,

with the alcoholtolform more tertiary butyl e."g. 51 0., preferably to about 20 C.

" vapors of the relatively volatile butyl chloride. During the progress of the condensation r'eacl chloride which'maylibe returned as raW'mat-I Theoretically 'sufiicient hydrogen chloride is 35 I rial for. carrying on the principal reaction} The givenoff in the principal reaction to produce inventiomthen, consists in the improved mama by reaction with the alcohol an amount-oi butyl hereinafter fully described and particularly chloride equal to that reacted in the first inpointediout in theclaims. I stance. Inpractice, however, some acid-must 40 Our improved methodinvolves a cyclic mode be added from another source to makeup for of operation consisting of two principal steps, losses in order to complete the cycle of operations viz.;- and maintain a balance between the various re- (1) In which tertiary butyl chloride andpheacting materials. In the reaction of the acid and nol are condensed, and alcohol water is produced, which is eliminated (2) In which hydrogen chloride evolved in from the system as a solution of hydrogen chlo- 46 Step (1) is absorbed in tertiary butyl alcohol to ride, thus accounting for a part of the losses of convert the latter to the corresponding chloride, the latter. The butyl chloride produced in the I the latterv then being-returned to step (1) as the second stage of the cycle is separated from the tertiary butyl chloride therein. I aqueous layer and may then be returned to the 50 The condensation reaction is carried out by first stage for reaction with phenol. 50 mixing tertiary-butyl chloride and phenol in ap- By operating in the cyclic manner just deproximately equimolecular proportions, together scribed we have found that the yield of tertiarywith about 0.25 to 1.0 per cent of a catalyst, e. g. butyl phenol on the butyl alcohol employed is inanhydrous FeCls or AlCl'z, in a suitable reactor creased as much as 10 per cent over that pre- I 5 provided with stirring means and with pipe coils viously obtainable. Furthermore, the hydrogen chloride produced in the condensation step is most economically and efficiently recovered and utilized by absorbing in butyl alcohol to produce more butyl chloride for continuing the process, thereby also avoiding necessity for separately recovering butyl chloride vapors from the acid gas. In the complete cycle the yield of tertiary-butyl phenol is to per cent on the tertiary butyl alcohol used, and to per cent on the phenol reacted.

Similar procedure may be followed in preparing homologous tertiary-alkyl-substituted phenols or aromatic hydrocarbons and derivatives thereof generally which are capable of being condensed with a tertiary alkyl halide to form'the corresponding tertiary alkyl substituted aromatic compound with accompanying evolution of gase- Such hydrogen halide,

ous hydrogen halide. which in practice may carry with it vapors of tertiary alkyl halide, may be absorbed in the corresponding tertiary alcohol to reproduce the tertiary alkyl halide directly without necessitating the use of heat or pressure or another chemical reagent to facilitate the reaction, and the tertiary alkyl halide so formed may then be used in the condensation reaction. '1

For example, we have carried out the condensation of benzene and tertiary butyl chloride in the presence of anhydrous aluminum chloride as catalyst to produce tertiary butyl benzene, absorbing the exit gases, consisting of hydrogen chloride and vapors of tertiary butyl chloride, in tertiary butyl alcohol to form additional tertiary butyl chloride, and then employing such formed and recovered chloride in the primary reaction. We have likewise condensed phenol with tertiary amyl chloride under similar conditions to those hereinbefore described, to formrtertiary' lar results may be obtained by reacting the tertiary alkyl bromide instead of the chloride, and absorbing the hydrogen bromide evolved in. the corresponding alcohol. In general, tertiaryalkyl-substituted aromatic compounds may be prepared in the manner described with the most economical recovery and reuse of gaseous prod ucts given off in the condensation reaction.

Other modes of applying the principle of our invention may be employed instead of the one explained, change being made as regards the method herein disclosed, provided the. step or steps stated by any of the following claims .or the equivalent of such stated step or steps be employed. 1

We therefore particularly point out and distinctly claim as our invention:

1. In a method of making a tertiary-alkyl-substituted aromatic hydrocarbon or derivative thereof wherein a tertiary alkyl halide is reacted with the aromatic compound, the improvement which consists in scrubbing the exit gases from the reaction with the tertiary alcohol corresponding to the alkyl halide employed.

2. In a method of making a tertiary-alkyl-substituted benzene derivative wherein a tertiary alkyl chloride is reacted with the benzene derivative, the improvement which consists in scrubbing the exit gases from the reaction with the tertiary alcohol corresponding to the alkyl chloride employed. 7

3. In a method of making tertiary-butyl phenol wherein tertiary butyl chloride is reacted with phenol, the improvement which consists in scrubbing the exit gases from the reaction with tertiary butyl alcohol.

. 4. A cyclic method of making a tertiary-alkylsubstituted aromatic compound which comprises reacting a tertiary alkyl halide with an aromatic compound to form the corresponding tertiaryalkyl-substituted. aromatic derivative, passing exit gases from the reaction, including hydrogen halide liberated thereby, into the tertiary alcohol corresponding to the alkyl halide employed, whereby to produce more of such halidegand returning such alkyl halide to the first step.w g

zene derivative, passing exit gases from'the re-,

action, including hydrogen chloride liberated thereby, into the tertiary alcohol corresponding to the alkylchloride employed, whereby to produce more of such chloride, and returning such alkyl chloride to the first step.

6. A cyclic method of making tertiary butyl phenol which comprises reacting tertiary butyl chloride with phenol, passing exit gases from the reaction, including hydrogen chloride liberated thereby, into tertiary butyl alcohol and returning the tertiary butyl chloride formed there-' by to the first step; v

'7. A cyclic' method of making tertiary-butylben'zene which comprises reacting tertiary butyl chloride with benzene, passing exit gases from the reaction, including hydrogen chloride liberated thereby, into a body of tertiary butyl alcohol and returning the tertiary butyl chloride formed thereby to the first step.

8. A cyclic method of making tertiary-amylphenol which comprises reacting tertiary amyl chloride with phenol, passing exit gases from the reaction, including hydrogen chloride liberated thereby, into a body of tertiary amyl alcoholand returning the tertiary amyl chloride formed thereby to the first step.

RALPH P. PERKINS. 7

ANDREW J DIE'IZLER. V JOSEPH T. LUNDQUIS'I'. 

